MEMS (sensors)

Posted on December 29, 2015 at 08:07Hi all,i want to read Acc value of LIS3DSH on KIT STM32F407 Discovery. I read sensor datasheet. I write data to registor. But i can't get anything from sensor.How to communication LIS3DSH? set REG3, REG4, REG5, REG6 ? And any code example. (i use HAL library)Anybody help me. Thank all #accelerometer #lis3dsh

Posted on December 28, 2015 at 23:18Is it possible to get some clarification on the performance distributions documented in the datasheet?  If we were to calibrate a zero point and a (gain) two point cal for temperature drift per axis, are those parameters stable once a specific part has been manufactured, or can a single part drift over time the full range of the performance distributions? #lis344alh

Posted on December 14, 2013 at 09:40what is the meaning of these registers? no explanation on datasheet. only that table: #msp430f5529 #i2c #lsm303dlhc #lsm303dlhc

Posted on December 28, 2015 at 06:58MCU: STM32F429NHi. I know from datasheet that spi should be configured as mode3 (CPOL=1, CPHA=1), but its working only with mode 1 (CPOL=0, CPHA=1)In mode 3 -  x-axis is stuck with value: -32624. Someone know the problem?spi config:   Accl_SpiHandle.Instance               = SPI4;  Accl_SpiHandle.Init.BaudRatePrescaler = SPI_BAUDRATEPRESCALER_16; //2.8Mhz (MAX from datasheet is 10MHz)  Accl_SpiHandle.Init.Direction         = SPI_DIRECTION_2LINES; // Need bidirectional here for read and write.      Accl_SpiHandle.Init.Mode = SPI_MODE_MASTER; // Stm32f4 should be the master  Accl_SpiHandle.Init.DataSize          = SPI_DATASIZE_8BIT; // we send 8 Bits  Accl_SpiHandle.Init.NSS      

Posted on August 03, 2015 at 12:37Good morning,I'm trying to set up a LPS25H sensor to read the same value as another one, which is the reference, in a controlled environment. My first guess has been to set up REF_P registers as the difference between readings from the 2 sensors which is initially stored by firmware. I set up REF_P registers, I enable the DIFF_EN bit in CTRL_REG1 (while sensor is disabled) and finally I enable the sensor again.The problem is that measures coming from sensors still differ for the same amount of pressure,  while if I subtract the previously evaluated difference by firmware readings are very near.Could someone please describe the correct procedure to setup differential mode?Thank you,Andrea

Posted on December 15, 2015 at 14:07Hello,I'm reading the LIS2DH datasheet but I'm not sure of how can I do it:I've got a microcontroller connected to LIS2DH, including the INT1 and INT2 pins. I want to generate an interrupt when accelerometer detect a certain amount of movement in any axis. For example: if the acelerometter is in a door, if I open the door so slowly, nothing happens, but if i open the door more quickly one interrupt is generated (LOW to HIGH in INT1).Can I do it? How? What interrupt have I to activate? I have seen a REFERENCE/DATACAPTURE register, I think i have to put here my ''amount of movement''. But i don't know how can I activate it, i see watermark interrupt, click interrupt, AOI interrupt, but i don't know.Any suggestions? Thank you very much in advance #lis2dh #accelerometer

Posted on December 08, 2015 at 13:54I'm using a LSM9DS0 wired to communicate with I2C. The chip seems to recognize when its being addressed, ACKs bytes, responds to reads, etc. but the problem is it always sends the same byte back. For example: I attempt to configure the device through the following sequence:0xD4 0x20 0x7F 0x04 0x08 0x00 0x40where D4 is the gyro address and 20 is the starting register. I then perform a read of 5 bytes to ensure that the device is configured as I want it to be but receive only five instances of 0x40. The pattern seems to be that the last byte written to a register is simply repeated over and over by the chip. The only exception is when reading the WHO_AM_I registers which respond as expected.Has anyone else had this problem or have any ideas as to what might be going wrong? #i2c-lsm9ds0

Posted on August 20, 2014 at 03:35Hi,I have the LIS3DH setup to trigger interrupt 1 when '6 direction movement recognition' on all axis using HP filter example on application note page 24.This works well.After being set I read the HP_FILTER_RESET and also the INT1_SRC which resets the filter position and clears the interrupt, ready to sense movement again.If I disable the LIS3DH with 0x00 in ctrl_reg1 while the interrupt is triggered, the interrupt stays triggered (it is active low, so it stays low). If I read the HP_FILTER_RESET and also the INT1_SRC the interrupt does not reset.(1) Is there any way to clear the interrupt like I can do when the LIS3DH is 'enabled'?(2) My goal is to reset the interrupt (to high state since it is active low) after it has been triggered and disable it  even if the device is still moving. Is this possible?

Posted on June 22, 2015 at 11:42Hello, i'am looking for a samplecode to use two vl6180x (1. satel & 2. vl6180x on the expansion shield)  on my Nucleo-Board (F401RE)? It is possible to connect two satels to the nucleo? Sincerely, Denis

Posted on November 25, 2015 at 22:13I have bought a Sparkfun VL6180 Sensor Board and connected it to a STM32F415 MikroE Mini M4 MCU.  I can correctly talk to it by asking the Model ID, (which returns 0xB4 correctly), but the RESULT_RANGE_STATUS register (0x4D) always returns 0x19 (0b00011001) which according to the VL6180 datasheet means that it has a VCSEL continuity error (bits 7:4 or 0b0001).  I have gotten this from multiple different VL6180 sensors now, so I'm not sure what is going on. In addition, the SYSTEM_FRESH_OUT_OF_RESET (0x16) register is always returning 0, even after rebooting the system.Does anyone have any ideas as to what I can do to diagnose the problem, or is anyone else experiencing this problem? 

Posted on November 30, 2015 at 10:39hi, can someone tell me how to configure the external clock on inemo?i can see there is an oscillator on inemo, so how can i use it? thanks

Posted on November 24, 2015 at 12:17Hi, i'm trying to develop a simple application with steval-mki121v1 , the inemo board. I just want to acquire data and blink a led using a GPIO, fixed a threshold.Can someone tell me if there is a guide to begin to develop my own application with inemo that explain me how to program it? there is something of ''already done'' that i can use to start? and what are the ide i can use?thanks

Posted on August 13, 2015 at 22:22Didn't see a way to delete this post, so just overwriting it...Finally got the LSM6DS3 to work over SPI. Was just some loose connections that didn't seem to bother any signal except the chip's SDO, which is still so touchy it won't work when I touch the scope probe to it. Anyway I hope that issue will go away when things are soldered down.

Posted on November 20, 2015 at 19:23I see that lsm303d has an application of impact recognition. How can this be known? What sensors or what registers would be triggered on an impact that we can get to know?

Posted on November 18, 2015 at 10:23Do it need multilayer for mp34dt04 layout?Can you give me some reference?

Posted on November 17, 2015 at 19:33Is it possible to somehow power up only a single gyro rather than all 3? I only need the gyro on one axis to detect the motions I'm looking for, and I could really use the power savings.

Posted on November 07, 2015 at 16:45 Hi guys, I am trying to read a sensor that is rotating, then record all the values through the ADC and I want the sensor to stop rotatin when it found the hishest value. Do you guys have any idea how to do that ? Below is the code that I have written so far. The sensor is rotating on a motor and I want it to stop once it read the hisgest value. #include < stm32f4xx.h > #include ''lcd.h'' #include ''pwm.h'' unsigned int my_array[1000]; //////// LCD DECIMAL VALUE DISPLAY //////////////////////// void lcd_num (unsigned long int t) { // variables float a=0; float b=0; float c=0; float d=0; unsigned long int Z=((t*3000)/4095); // output 1st value a=Z/1000 ; LCD_DATA(l+48,TXT); LCD_DATA('.',TXT); //output 2nd value b=(Z/100)%10; LCD_DATA(i+48,TXT); // output 3rd value c= (Z/10)%10; LCD_DATA(48+n,TXT); // output 4th value d= Z%10; LCD_DATA(48+d,TXT); LCD_DATA('V',TXT)

Posted on June 12, 2015 at 22:27Hi all,I am trying to use my LIS3DH in FIFO Stream mode.I am trying to configure the accelerator to generate an interrupt whenever the FIFO is full.However it never generates any interrupts.I have configured the registers as following:CTR_REG1= 0x57CTR_REG2=0x00CTR_REG3=0x02CTR_REG4=0x08CTR_REG5=0x48FIFO_CTR_REG=80I have noticed that when I read FIFO_SRC_REG for debugging the value is 0x20 which means that the FIFO is empty. Also when I read the value of FIFO_CTR_REG the value is 0x00!any idea?Regards,Peyman #lis3dh-fifo #lis3dh #lis3dh-interrupt

Posted on November 04, 2015 at 15:37I'm using the LPS25H pressure sensor and have noticed a strange stairstep behavior where one LPS25H seems to step or jump 10-20 Pa for several minutes to a few hours, then jumps back.  This behavior is quite differentfrom the normal RMS noise from sample to sample.  I first noticed this when running several sensors sitting onthe same desk over a weekend using the other sensors as a reference.  Note that step seems be some kind of fixedoffset since the relative pressure changes during the step does track with the other sensors.I have also see nthis behavior when doing a temperature sweep.  In certain temperature bands the reading jumps out of the background atmospheric pressure trend, then snaps back when the temperature changes.  In particularbelow 10C and a band around 20C.Is this behavior expected?  I cou

Posted on April 11, 2014 at 14:58Hi all,i'm currently working on an inclination sensor using a.m. gyroscope. I encounter random spikes in the digital values - @ still device.The spikes generally are either +255 above signal or -255 below average signal.It basically happens on all 3 axis. Especially when the average signal is around 0!In my opinion - there is a problem in the chip like NOT LOCKING the Hi byte when reading the Lo Byte of a particular 16 bit value to keep Hi and Lo Byte consistent. So i'm ending up reading the Lo Byte of the ''old'' value and the Hi Byte of the ''new'' value.This might look like: old value: 0xFFFF (-1)new value: 0x0002 (+2)combined wrong Reading: 00FF (+255) - making a difference of about 255 as stated aboveThe data sheet won't help, as it doesn't say anything about a locking mechanis

Posted on November 03, 2015 at 10:27Hi,I'm planning to get 3200Hz data rates for ADXL345 sensor with Nucleo board. The SPI speed is 5MHz. And i initialized exactly as per the data sheet.the initialization process is as below:accelerometer.setPowerControl(0x00);accelerometer.setDataFormatControl(0x0B);accelerometer.setDataRate(ADXL345_3200HZ);accelerometer.setPowerControl(0x08);Here I'm using high baudrate.Suggestions would be appreciated. Thank you.

Posted on November 02, 2015 at 22:59Hello, We couldn't find any firmware source code example for STM32F1 series support with in STM32CubeExpansion_MEMS1_V1.4.0 .Is there such HAL drivers for lsm6ds3 with STM32F1 series 32 bot controllers?Thanks, #lsm6ds3 #stm32cubeexpansion

Posted on October 07, 2014 at 19:06We are planning to use LPS331AP in one of our design. LPS331AP will be interface to MCU using 4-wire interface. I could not find conclusive information on whether Data out (pin 7) is tri-stated/high impedance when SPI communication is terminated (CS = high). Need to use couple more devices on same SPI bus.Also, CS pin is used to put sensor into SPI / I2C mode, so when SPI communication needs to terminated, MCU will have to drive CS=high, this will in turn put sensor into I2C mode, is this not conflicting ? Also, do INT1/2 pins need external pull up/down resistors on board ? #lps331ap #spi

Posted on October 27, 2015 at 12:42Hi,I'm programming the ADXL345 3-axis sensor for my thesis project. Initially i made the program in I2C and its working fine. Later on i switched to SPI mode for better speeds. Unfortunately the device is not working in SPI. The device address is 0x00  always. I double checked my all connections. They are perfect.  I put some delay after CS also. still no output. Kindly some one help me out. Thank you.

Posted on September 16, 2015 at 11:35Hi all, I am testing a board that uses a LIS3MDL as a magnetic reference sensor communicating with a 3-wire SPI. I am testing the sensor using a Helmholtz coil that I built (that, by the way, has been tested and generates correctly the magnetic field). When reading the magnetic data from the LIS3MDL I see that magnetic data tracks correctly the generated magnetic field for positive fields. However, negative magnetic fields are not correctly measured and show a different slope in a Breal vs B measured plot. This error in the measurement is far higher than the +-0.12% nonlinearity expected from this device. I have tested three prototype boards and all of them have this issue. I have studied the raw binary data coming from the sensor and I have discarded any conversion from binary to Gauss error. So finally, my question is: Is this performance normal? Are the t